1. Field of the Invention
The present invention relates to navigation systems generally and more particularly to visual navigational aids. Specifically, the present invention is concerned with personal aviation navigation systems.
2. Description of Related Art
The following U.S. patents are believed to represent the current state of the art: U.S. Pat. Nos. 6,809,724; 6,798,391; 6,771,423; 6,757,068; 6,747,611; 6,727,865; 6,681,629; 6,661,438; 6,608,884; 6,563,648; 6,559,872; 6,474,159; 6,408,257; 6,384,982; 6,380,923; 6,359,609; 6,356,392; 6,353,503; 6,304,303; 6,222,677; 6,204,974; 6,157,533; 6,140,981; 6,127,990; 6,108,197; 6,094,242; 6,057,966; 6,050,717; 5,886,822; 5,880,773; 5,844,656; 5,798,733; 5,764,280; 5,581,492 and 5,757,339.
The following patent publications are also believed to be of interest: Published PCT Applications: W004015369; W002086590; W00180736; W00156007; W00116929; W00109636; W00023815; W00010156; W09733270; W09725646; W09637798; W09636898; W09607947; W09605532; W09600406; W09521395; W09510106; W09510061; W09424658; W09414152; W09411855; W09407161 and W09301683.
Foreign Patent Publications: EP 1310859; EP 1280457; EP 1267197; EP 1248180; EP1223729; EP1220080; EP1185142; EP1176449; EP1135765; EP1042698; EP1022644; EP0935183; EP0904560; EP0902312; EP0889346; EP0825470; EP0802440; EP0775327; EP0772790; EP0771433; EP0724758; EP0721614; EP0716329; EP0694196; EP0670537; EP0672286; EP0627644; EP0592591 and EP0344881.